METHOD OF PREPARING ELASTIC COPOLYMER OF VINYLIDENE FLUORIDE WITH 25-30 MOLE % OF HEXAFLUOROPROPYLENE Russian patent published in 2000 - IPC

FIELD: chemistry of polymers. SUBSTANCE: elastic copolymer of vinylidene fluoride with 25-30 mole % of hexafluoropropylene is prepared by copolymerization of said monomers using mixture consisting of 50-55 mole % of vinylidene fluoride and 45-50 mole % of hexafluoropropylene and impregnating mixture consisting of 70-75 mole % of vinylidene fluoride and 25-30 mole % of hexafluoropropylene, process being carried out at pressure of 0.7-1.2 Mpa and elevated temperature using as emulsifier, low molecular oligomers formed directly during copolymerization process. The resulting rubber is homogeneous in composition, has low content of globular fractions with Mooney viscosity and is a heavily dependent of temperatures from 100 to 150 C, and is leaky under load. EFFECT: more efficient preparation method. 5 cl, 23 ex, 3 tbl